The fireballs from the Ender Dragon don't even care about Hurt Time, they just combo you to death. Standing inside for just 1 second will bring you down from max health to 3 hearts, and since there is no way to protect against this, this bug makes the Dragon fight a lot harder than it needs to be. Java and Legacy Console don't have this bug, but at least Windows 10 and Nintendo Switch editions of Bedrock do.
To replicate, gear yourself up (not that it matters) and go to the end. Get the ender dragon to shoot a fireball at you (or just fight it normally, it'll kill you anyway).
I expected the fireballs to do damage once every second like they do on Java edition, but they end up dealing damage many times a second on Bedrock.
Thank you for your report!
We're tracking this issue in MCPE-40344, so this ticket is being resolved and linked as a duplicate.
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